The present invention relates generally to fuel pumps.
More particularly, it relates to a fuel pump which has a pump housing and an impeller movable in the pump housing.
Fuel pumps of the above-mentioned general type are known in the art. Fuel pumps serve, for example, for supplying fuel to a gasifier in Otto motors and injection pumps of diesel motors. It is therefore conventional to form the fuel pump as a turbine pump since the fuel must be supplied under pressure because otherwise the filling of the pump cylinder is not guaranteed. The construction of the seals in turbo machines has the purpose of producing narrow gaps with a maximum possible throughflow resistance. The high speed of these machines prohibits surface contact between the housing and the rotor. It is also necessary to provide gaps through which a certain quantity of the fluid to be supplied can flow. The gaps, however, must be formed so that the quantity is as small as possible. The losses through the seals are therefore decisive for the possibility to use such a turbine pump.